Abstract:Reactions to gamma-irradiation in an acute dose of 750 R in C57BL/6, 101/Hf and С3H/Sn mice at different physiological levels were analyzed. In C3H/Sn and 101/Hf mice, light scattering spectrum was shifted towards small particles, while in C57BL/6 mice increased contribution of large particles was observed. In 3 weeks, a shift towards larger particles was recorded in all three mouse strains, but its degree varied. By week 6, the histograms approached the control. Histological study showed that the incidence of severe injuries in the liver increased by the end of the experiment in C57BL/6 mice (but not in other mouse strains). The same shifts were observed in the pancreas and an opposite tendency was seen in the spleen. Thus, C57BL/6 mice responded to irradiation later that C3H/Sn and 101/Hf mice, but demonstrated high adaptation capacity. C3H/Sn mice best of all recovered from the radiation crisis.